Self-assembly and entropic effects in pear-shaped colloid systems. II. Depletion attraction of pear-shaped particles in a hard-sphere solvent

ABSTRACTWe have developed a highly modular electrostatically-mediated approach to colloid-colloid and polymer-colloid networks using ‘building block’ and ‘bricks and mortar’ self-assembly methodologies, respectively. The former approach involved functionalization of one type of nanoparticle building block with a primary amine and a counterpart building block with a carboxylic acid derivative. After combining these two systems, acid-base chemistry followed by immediate charge-pairing resulted in the spontaneous formation of electrostatically-bound mixed-nanoparticle constructs. The shape and size of these ensembles were controlled via variation of particle size and stoichiometries. In the ‘bricks and mortar’ approach, a functionalized polymer is combined with complementary nanoparticles to provide mixed polymer-nanoparticle networked structures. A notable feature is the inherent porosity resulting from the electrostatic assembly. The shape and size of these ensembles were controlled via variation of particle size, stoichiometries and the order in which they were added.

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Hard sphere structural effects in colloid systems

Chemical Physics Letters ◽

10.1016/0009-2614(77)80397-7 ◽

1977 ◽

Vol 51 (2) ◽

pp. 257-260 ◽

Cited By ~ 25

Author(s):

D.John Mitchell ◽

Barry W. Ninham ◽

Bernard A. Pailthrope

Keyword(s):

Hard Sphere ◽

Structural Effects ◽

Colloid Systems

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Self-assembly mechanism in colloids: perspectives from statistical physics

Open Physics ◽

10.2478/s11534-012-0019-x ◽

2012 ◽

Vol 10 (3) ◽

Cited By ~ 1

Author(s):

Achille Giacometti

Keyword(s):

Integral Equation ◽

Self Assembly ◽

Hard Sphere ◽

Statistical Physics ◽

Colloidal Particles ◽

Building Blocks ◽

Computational Effort ◽

Spherical Particles ◽

Square Well ◽

Patchy Colloids

AbstractMotivated by recent experimental findings in chemical synthesis of colloidal particles, we draw an analogy between self-assembly processes occurring in biological systems (e.g. protein folding) and a new exciting possibility in the field of material science. We consider a self-assembly process whose elementary building blocks are decorated patchy colloids of various types, that spontaneously drive the system toward a unique and predetermined targeted macroscopic structure. To this aim, we discuss a simple theoretical model — the Kern-Frenkel model — describing a fluid of colloidal spherical particles with a pre-defined number and distribution of solvophobic and solvophilic regions on their surface. The solvophobic and solvophilic regions are described via a short-range square-well and a hard-sphere potentials, respectively. Integral equation and perturbation theories are presented to discuss structural and thermodynamical properties, with particular emphasis on the computation of the fluid-fluid (or gas-liquid) transition in the temperaturedensity plane. The model allows the description of both one and two attractive caps, as a function of the fraction of covered attractive surface, thus interpolating between a square-well and a hard-sphere fluid, upon changing the coverage. By comparison with Monte Carlo simulations, we assess the pros and the cons of both integral equation and perturbation theories in the present context of patchy colloids, where the computational effort for numerical simulations is rather demanding.

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Effect of self-assembly in water-containing colloid systems with dispersed mineral particles on their structural mechanical characteristics

Journal of Water Chemistry and Technology ◽

10.3103/s1063455x17060066 ◽

2017 ◽

Vol 39 (6) ◽

pp. 346-350

Author(s):

V. V. Goncharuk ◽

L. V. Dubrovina ◽

E. V. Makarova

Keyword(s):

Self Assembly ◽

Mechanical Characteristics ◽

Mineral Particles ◽

Colloid Systems

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Entropic effects in the self-assembly of open lattices from patchy particles

Physical Review E ◽

10.1103/physreve.87.062319 ◽

2013 ◽

Vol 87 (6) ◽

Cited By ~ 17

Author(s):

Xiaoming Mao

Keyword(s):

Self Assembly ◽

The Self ◽

Patchy Particles ◽

Entropic Effects

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Towards the colloidal Laves phase from binary hard-sphere mixtures via sedimentation

Soft Matter ◽

10.1039/c8sm00237a ◽

2018 ◽

Vol 14 (13) ◽

pp. 2465-2475 ◽

Cited By ~ 6

Author(s):

Tonnishtha Dasgupta ◽

Marjolein Dijkstra

Keyword(s):

Self Assembly ◽

Hard Sphere ◽

Laves Phase

Self-assembly route for the photonic colloidal Laves phase via templated sedimentation.

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In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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The Nature of Rapidly Extracted Phycocyanin from the Blue-Green Alga Plectonema Boryanum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065870 ◽

1971 ◽

Vol 29 ◽

pp. 366-367

Author(s):

M. Kessel ◽

R. MacColl

Keyword(s):

Self Assembly ◽

Analytical Ultracentrifugation ◽

Uranyl Acetate ◽

The Self ◽

Major Protein ◽

Subunit Structure ◽

Blue Green Alga ◽

Thin Sections ◽

Blue Green Algae ◽

Cacodylate Buffer

The major protein of the blue-green algae is the biliprotein, C-phycocyanin (Amax = 620 nm), which is presumed to exist in the cell in the form of distinct aggregates called phycobilisomes. The self-assembly of C-phycocyanin from monomer to hexamer has been extensively studied, but the proposed next step in the assembly of a phycobilisome, the formation of 19s subunits, is completely unknown. We have used electron microscopy and analytical ultracentrifugation in combination with a method for rapid and gentle extraction of phycocyanin to study its subunit structure and assembly.To establish the existence of phycobilisomes, cells of P. boryanum in the log phase of growth, growing at a light intensity of 200 foot candles, were fixed in 2% glutaraldehyde in 0.1M cacodylate buffer, pH 7.0, for 3 hours at 4°C. The cells were post-fixed in 1% OsO4 in the same buffer overnight. Material was stained for 1 hour in uranyl acetate (1%), dehydrated and embedded in araldite and examined in thin sections.

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